Answer:
is the compression in the spring
Explanation:
Given:
- mass of the bullet,

- mass of block,

- stiffness constant of the spring,

- initial velocity of the spring just before it hits the block,

<u>Now since the bullet-mass gets embed into the block, we apply the conservation of momentum as:</u>



Now this kinetic energy of the combined mass gets converted into potential energy of the spring.



is the compression in the spring
Theoretically, the light ray will not change direction. The center of a lens is called the optical center. If the ray of light hits the lens even just a little bit off center, the light ray is refracted. Refraction happens when the incident and exit angles of the ray are different. The optical center is guaranteed to not have any difference in angle, which allows the light ray to pass through directly without changing direction.
Answer:
when a magnet is hanged freely in air it turns in the direction of the north and south while the magnetic north pole faces the south pole of the earth and magnetic south pole faces the north pole if the earth
Answer:
c) Water molecules melt into gas molecules.
The number of electrons emitted from the metal per second increases if the intensity of the incident light is increased.
Answer: Option B
<u>Explanation:</u>
As a result of photoelectric effect, electrons are emitted by the light incident on a metal surface. The emitted electrons count and its kinetic energy can measure as the function of light intensity and frequency. Like physicists, at the 20th century beginning, it should be expected that the light wave's energy (its intensity) will be transformed into the kinetic energy of emitted electrons.
In addition, the electrons count emitting from metal must vary with light wave frequency. This frequency relationship was expected because the electric field oscillates due to the light wave and the metal electrons react to different frequencies. In other words, the number of electrons emitted was expected to be frequency dependent and their kinetic energy should be dependent on the intensity (constant wavelength) of light.
Thus, the maximum in kinetic energy of electrons emitted increases with increase in light's frequency and is experimentally independent of light intensity. So, the number of emitted electrons is proportionate to the intensity of the incident light.